Computational investigation of heat load and secondary flows near tip region in a transonic turbine rotor with moving shroud

The purpose of this paper is to investigate numerically the effect of the relative shroud motion on both the heat transfer and secondary flows near the tip of a transonic turbine blade. The simulations are done by solving the compressible Reynolds averaged Navier-Stokes (RANS) equations using the finite volume method implemented in the Fluent CFD software. The investigated rotor blade geometry was designed by SNECMA for modern aeroengines. The computational grid is created using multi-block topology and each block support a structured mesh. Calculations are done under a transonic flow regime for both stationary and moving shroud cases. The aerothermal properties and flow topology at the blade tip, the shroud and the blade suction surface are compared with and without shroud movement. The relative motion has significantly changed the distribution and the level of the heat transfer coefficient, the pressure coefficient, the isentropic Mach number and the flow topology.